The LHCb Scintillating Fibre (SciFi) Tracker is designed to replace the current downstream tracking detectors in the LHCb Upgrade during the shutdown 2019 to 2020. It is based on 2.5 m long and 0.250 mm diameter scintillating fibres as the active medium. Silicon photomultiplier arrays with 128 channels and 0.25 mm channel width are used for readout. The front-end electronics are based on a custom ASIC chip, the PACIFIC, and an FPGA for the hit clustering with a readout rate of 40 MHz.

The assembly and commissioning of the SciFi Tracker is underway. Milestones and challenges in operating and monitoring the detector together with latest performance results will be presented.